Carotid ultrasound usually is done in a doctor's office or hospital. The test is painless and often doesn't take more than 30 minutes.
The ultrasound machine includes a computer, a screen, and a transducer. The transducer is a hand-held device that sends and receives ultrasound waves.
You will lie on your back on an exam table for the test. Your technician or doctor will put gel on your neck where your carotid arteries are located. The gel helps the ultrasound waves reach the arteries.
Your technician or doctor will put the transducer against different spots on your neck and move it back and forth. The transducer gives off ultrasound waves and detects their echoes as they bounce off the artery walls and blood cells. Ultrasound waves can't be heard by the human ear.
The computer uses the echoes to create and record pictures of the insides of the carotid arteries. These pictures usually appear in black and white. The screen displays these live images for your doctor to review.
Your carotid ultrasound test might include a Doppler ultrasound. Doppler ultrasound is a special test that shows the movement of blood through your arteries. Blood flow through the arteries usually appears in color on the ultrasound pictures.